65 vette dude

Set of NOS OFF ROAD mufflers and pipes bought at a Chevy dealer in the seventies on EBAY. Item #160161121420. Looks like the real deal......if interested, call your stock broker.

Joel 67

It will be interesting to see what these go for. I am sure the current bid of $510 is just the beginning.

http://cgi.ebay.com/ebaymotors/ws/eB...link:middle:us

philip964

Ok for the dummies like me, what were these really for? Did people really go off roading in their Corvettes, or was this a GM way to get a loud muffler for the smart buyer. A Corvette muffler is so low anyway were they designed not to start grass fires?

I guess if you have a tank sticker and it says your car came with this - your going to have to bid. Does this add alot to the value of your car?

Equal to a big tank or a radio delete?

Injected Stingray

The N-11 was a welded system at the back instead of the clamps and had three baffles in the muffler instead of the standard five. It was available on L-75,L-76 and L-84 cars in 64 and more in 65. I would love to have that system for my Fuelie but im sure it will go for more than i want to spend now that it's posted here. There were 1,953 cars equipped with this system in 64 so it's not that rare but exhaust don't last that long so all the GM stuff is gone. If i bought this it would only go on for shows because of the rust issues.

vark_wso

Back in ancient times, I bought a set of these at a Chevy dealer parts counter. The pipes were double-wall; that is, a pipe within a pipe then mandrel bent, flattened bottoms, etc. Very likely that this construction contributed to the unique sound note & is perhaps why none of the aftermarket guys have been able to represent that sound with their 'repro' off-road systems. As I recall, the mufflers very quickly rusted from the inside in the vicinity of the low forward end.

mts7900

I'm not an expert on SCCA rules, but I think that after 1964 some of the rules changed and included noise restrictions for some courses, requiring mufflers. Chevy came out with N11 in 1964.

I have an original set on my car, and they are super loud. They sound a bit different than the side exhaust.

The N11 system isn't for driving on grass

JohnZ

All factory-installed Corvette under-car exhaust systems had the intermediate pipe (from the trans crossmember back) welded to the muffler inlet; that's how they were received at St. Louis. For Service, the standard system mufflers had the curved inlet pipe and used clamps at the connection to the (cut off) end of the intermediate pipe in front of the spare tire tub. The N-11 Service replacement was the exception - it was supplied in Service exactly as it was to St. Louis, with the long intermediate pipe welded to the muffler.

An NOS pair of N-11 muffler assemblies went last week on eBay for $5900.00.

gonefishn

Hate to bring it up again, but a true reproduction of the N11 exhaust would be lucrative (most under car exhaust people would by them, wearable item so repeat customers, could be fitted to other vehicles,...).

If I was in the exhaust businees, or retired, or had more time I'd buy the set and reproduce it.

My friend has a set and nothing sounds better

Injected Stingray

Thanks for the clarification on that John. Do you know of any way to identify a factory N-11 equipped car other than original docs.

$5900.00 for a exhaust that's going to rust out is not in my budget right now, that's almost what I payed for the car.

mts7900

According to the Nolan Adams Rest Guide you're not correct. What documented information do you have that states the intermediate pipes were welded to mufflers on all exhaust systems?

JohnZ

The information in the first paragraph of the N-11 section on page 238 in Noland's book is incorrect. If you'll check the "Exhaust" sections for each year in Noland's book, and in UPC 8 of all the midyear assembly manuals, you'll see that the intermediate pipe and muffler are an "assembly", with one part number, and there are no clamps. Clamps were only used in Service, when the mufflers were replaced; Service mufflers (except N-11) were supplied with the curved inlet pipe and a clamp where the inlet pipe fit over the the cut-off end of the intermediate pipe.

mts7900

Being at odds with Noland Adam's guide is one thing, but relying on the assembly manual to define this doesn't make Nolands book incorrect. The assembly manual identifies the left and the right mufflers and intermediate pipes as one COMPLETE assembly (for both sides as one assembly). It doesn't define how the mufflers and intermediate pipes are assembled. Even an assembly line photo, if one exists, won't clear this disagreement up, without knowing exactly which exhaust system would be shown.

JohnZ

No, it doesn't. In all cases, there is a right-hand assembly, and a left-hand assembly; the item number in the box is followed by TWO part numbers (like "3859561-2 Muffler & Rear Exhaust Pipe Asm, L & RH"). 3859561 is the left side assembly, and 3859562 is the right side assembly.

I worked at St. Louis in '67-'68; my Production Engineering group was responsible for developing the assembly processes and tooling, and I know just a little about it.

mts7900

As an Engineer myself, I know you're correct in stating that when left and right hand assembly are created, they have seperate engineering part numbers assigned, but I'll say this again, the Assembly Manual only identifies ONE PART NUMBER for both sides, not 2 part numbers. You may know more about this than we do, but you haven't shown any documentation to contradict Noland Adam's book.

66L72

and Noland will acknowledge the odd error in his "bibles as well.

i would take john's knowledge base and memory over both published sources

mts7900

His knowledge is valuable, but nowhere in this conversation is it defined that standard mufflers and intermediate pipes are welded assemblies. We're taking JohnZ at his word vs Adam's written guide.

Crazyhorse

Well Corvette Central also agrees........

"Original factory exhaust systems came on the car with the secondary pipe welded to the muffler"

Bottom of this page ...

http://www.corvettecentralexhaust.com/c2stocksys.htm

66since71

I replaced the original stock mufflers (not N-11) on my 66 back in 1972 or 73. I had to saw off the old muffler, just as JohnZ describes. The intermediate pipe and muffler were a single welded assembly. I still have those pipes under the deck, compolete with hack saw cuts.

IGO200

I had them on my '65 365. They were welded (I remember sawing them off when I went to side pipes) and they sounded BAD ***.....
But I just HAD to have those side pipes!

Alan 71

John knows Corvettes . John knows how Corvettes were assembled.
John remembers more than most of us have forgotten. John has pictures of things and places most of us have never seen. John is respectful in all his posts , even when he's answering a question he's answered many times before.
No , I'm not on his payroll.
Regards,
Alan